A method for reducing vibration of inclined hole trenching blasting

Abstract

The application provides a method for reducing vibration by slanting blast hole trenching blasting, which sets a starting blasting area in front of a main blasting area, and specifically comprises the following contents: (1) at least five rows of blast holes with equal depth are set in the starting blasting area, and a blast hole in the middle is taken as a middle row; all the blast holes are slanting blast holes; one half-blast hole is set in the middle row; the blast holes on both sides of the middle row are slanting blast holes which are inclined to a reference surface; (2) the total charge amount of the blast hole in the middle row is 50-60% of the hole depth; the total charge amount of the half-blast hole is one third to one half of the hole depth; the total charge amount of the blast holes on both sides of the middle row is 45-50% of the hole depth; (3) the half-blast hole is first blasted, then the blast holes in the middle row are blasted one by one, and finally the other blast holes in the starting blasting area are blasted one by one; when blasting the blast holes in the starting blasting area, the blast holes are blasted one by one with time delay. The technical scheme of the application can effectively reduce the blasting vibration intensity.

Description

Technical Field

[0001] The present invention relates to the technical field of mining blasting, and particularly to a vibration reduction method for inclined hole trenching blasting. Background Art

[0002] Open-pit bench deep-hole blasting is an important production link in open-pit mine mining and the center of mine production organization. Practice shows that in open-pit deep-hole blasting, the following laws are summarized as the number of free faces increases:

[0003] (1) The peak value of the particle vibration velocity of the blasting seismic wave decreases;

[0004] (2) The main frequency of the blasting seismic wave increases, the main shock frequency band becomes wider, and the frequency domain components increase;

[0005] (3) The peak energy of the blasting seismic wave decreases.

[0006] From the energy perspective, the role of the free face in the rock-breaking mechanism of rock mass blasting is analyzed, and then the influence of the free face on the parameters of the blasting stress wave is analyzed and studied. The results show that the existence of the free face changes the distribution characteristics of the explosion energy, resulting in an increase in the crushing energy and a corresponding decrease in the blasting vibration energy; the free face will cause the peak stress of the blasting stress wave to decay faster and the peak particle velocity to decay slower.

[0007] Compared with other blasting methods, deep-hole blasting is convenient for operations such as drilling and crushing. The crushing quality of deep-hole blasting is relatively good, and the muck pile is relatively concentrated. Due to these characteristics, in blasting production, not only the mechanization degree is high, which greatly reduces the labor intensity, but also the loading and unloading progress can be accelerated, the production efficiency can be improved, the engineering cost can be reduced, and it is suitable for large-scale production. However, the vibration generated by deep-hole blasting is more likely to cause cumulative damage to the rock mass in the slope. For engineering sites that often use deep-hole blasting, the mechanical strength of the surrounding rock mass is significantly reduced. If not protected in time, there will be potential safety hazards.

[0008] In actual production blasting, it is often necessary to control the blasting vibration to reduce the damage to the slope where it is located and the impact on surrounding buildings and structures. However, there must be trenching blasting without a horizontal free face. If effective measures cannot be taken, the consequences caused by this blasting vibration need a large number of subsequent measures to make up for, consuming manpower and financial resources. For example, excessive blasting vibration may induce slope sliding, which requires increasing the investment in slope treatment. It has a great impact on residential buildings and requires compensation and appeasement of residents. Summary of the Invention

[0009] In open-pit deep-hole blasting, aiming at the problem of reducing blasting vibration without a horizontal free face, the present invention proposes a vibration reduction method for inclined hole trenching blasting, which can add a horizontal free face and thus reduce the intensity of blasting vibration.

[0010] The technical means employed in this invention are as follows:

[0011] A method for vibration reduction during blasting in inclined borehole trenching involves setting up an initial blasting zone in front of the main blasting zone, specifically including the following:

[0012] (1) Hole Design

[0013] At least five rows of blast holes of equal depth are set in the initial blasting area, with the middle row of blast holes serving as the intermediate row; in the initial blasting area, all blast holes are inclined blast holes, and the blast holes in the same row are parallel to each other.

[0014] On the side of the middle row away from the main blasting area, a half-shot hole is set. The depth of the half-shot hole is 1 / 2 + 1 to 2m of the depth of other holes in the initial blasting area. The holes in the middle row and the half-shot holes are all inclined holes that slope towards the main blasting area. The half-shot holes are parallel to the holes in the middle row.

[0015] With the middle row as the reference plane, the blast holes on both sides of the middle row are inclined blast holes that are inclined toward the reference plane on a vertical plane perpendicular to the reference plane.

[0016] The horizontal component of the inclination direction of the boreholes in the middle row and the half-bore boreholes is consistent with the strike direction of the rock strata, while the horizontal component of the inclination direction of the boreholes on both sides is perpendicular to the strike direction of the rock strata.

[0017] (2) Charge design

[0018] For the boreholes in the middle row, the total charge is 50-60% of the borehole depth. When charging, spacer material is used as a spacer. The charge in the lower section is 60-65% of the total charge, and the charge in the upper section is 35-40% of the total charge.

[0019] For half-holes, the total charge is one-third to one-half of the hole depth, and a coupled charging method without segmentation is used.

[0020] For the boreholes located on both sides of the middle row, the total charge is 45-50% of the borehole depth. When charging, spacer material is used as a spacer. The charge in the lower section is 60-65% of the total charge, and the charge in the upper section is 35-40% of the total charge.

[0021] (3) Detonation sequence design

[0022] When blasting any blast holes other than half-cut blast holes within the initial blasting area, the upper section is blasted first, followed by the lower section, with an interval of 40-65ms between the upper and lower sections.

[0023] The detonation sequence is as follows: first, detonate half of the blast hole; then, detonate the upper section of the middle row of blast holes located in the first row; and finally, detonate the lower section of the middle row of blast holes located in the first row and other blast holes within the initial blasting area segment by segment.

[0024] The total number of blasts in the initial blasting area is 1+2n, where n represents the number of blast holes in the initial blasting area excluding half-hole blast holes; the blasting process adopts delayed blasting, and the interval between two consecutive blasts is 11-36ms; during the blasting process, the interval time cannot be the same continuously, and the time interval between the middle or the last (1 / 2 to 3 / 4)*(1+2n) blasts is 11-15ms.

[0025] Furthermore, the distance between the upper end of each borehole located on both sides of the middle row and the reference surface is wider than the distance between the lower end and the reference surface.

[0026] Furthermore, the boreholes in the middle row are spaced 1 to 2 meters apart when loading explosives; the boreholes on both sides of the middle row are spaced 1 to 1.5 meters apart when loading explosives.

[0027] Furthermore, the inclination angle of the blast holes in the initial blasting area is 70-80°; the diameter d of the blast holes in the initial blasting area is 900-250mm; the depth (step height) of the blast holes in the initial blasting area, except for the half-hole blast holes, is >10m; the distance b between the upper ends of two adjacent rows of blast holes in the initial blasting area is (20-30)*d, and the distance a between the upper ends of two adjacent columns of blast holes is (20-30)*d; in the initial blasting area, the distance between the lower ends of two adjacent columns of blast holes located on the same side of the middle column is (10-12)*d.

[0028] Furthermore, the spacer material used during loading is rock debris or crushed 1-2 cm pebbles.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] The vibration reduction method for inclined blast hole trenching provided by this invention has good blasting effect, good blast pile shape, good fragmentation effect, significantly fewer large pieces, and less perceptible vibration. It can reasonably control the blasting power and blasting vibration. The vibration data value of the blasting test is low and the vibration is not obvious. After adjusting the delay parameter, the vibration intensity can be controlled to gradually decrease to 0.26cm / s, which is far below the vibration safety standard of "Blasting Safety Regulations GB6722-2014".

[0031] Based on the above reasons, this invention can be widely applied in the field of mining blasting technology. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart of the inclined blast hole trenching and blasting vibration reduction method described in this invention.

[0034] Figure 2 This is a schematic diagram of the borehole arrangement described in this invention.

[0035] Figure 3 This is a schematic diagram of the boreholes in the middle row of the present invention.

[0036] Figure 4 This is a schematic diagram of the blast holes located on both sides of the middle row as described in this invention.

[0037] Figure 5 This is a schematic diagram of the area defined by the borehole opening and bottom of the present invention.

[0038] Figure 6 This is a schematic diagram of the borehole detonation sequence described in this invention.

[0039] In the diagram: 1. Half-shot blast hole; 2. Blast holes in the middle row; 3. Blast holes located on both sides of the middle row; 5. Lower section; 6. Upper section. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0043] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of the invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following figures denote similar items; therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0044] In the description of this invention, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is generally based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0045] For ease of description, spatial relative terms such as "above," "over," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation besides the orientation of the device as described in the figures. For example, if the device in the figures is inverted, a device described as "above" or "above" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0046] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore should not be construed as limiting the scope of protection of this invention.

[0047] Example 1

[0048] Currently, the Sadovsky formula is commonly used to predict the peak blasting velocity in each section, as shown in the following formula:

[0049]

[0050] In the formula: v is the peak particle vibration velocity (cm / s); Q is the charge per blast (kg); r is the distance from the blast center (m); K and α are coefficients related to the blasting method and site conditions, and are closely related to the blasting method, charge structure, and topographic and geological conditions between the blasting point and the calculation point. When the number of blasting free faces increases, K and α will decrease significantly, and the blasting vibration velocity will also decrease significantly.

[0051] like Figure 1 As shown, this invention provides a method for vibration reduction during blasting in inclined borehole trenches, wherein an initial blasting zone is set up in front of the main blasting zone, specifically including the following:

[0052] (1) Hole Design

[0053] like Figure 2 As shown, at least five rows of blast holes of equal depth are set in the initial blasting area, with the middle row of blast holes serving as the intermediate row; in the initial blasting area, all blast holes are inclined, and the blast holes in the same row are parallel to each other.

[0054] like Figure 3As shown, a half-borehole 1 is set on the side of the middle row away from the main blasting area. The depth of the half-borehole 1 is 1 / 2 + 1 to 2m of the depth of other blast holes in the initial blasting area. The half-borehole is blasted first because the horizontal component of the inclined blast hole is consistent with the rock orientation, and it can provide a free surface for the blasting of other blast holes more than blast holes with other orientations. The blast holes 2 in the middle row and the half-borehole 1 are both inclined blast holes that are inclined towards the main blasting area. The half-borehole 1 is parallel to the blast holes 2 in the middle row. Since vertical blast holes only have one horizontal free surface at the top, vertical blasting will produce a large vibration intensity. However, choosing inclined blasting will make reasonable use of the free surface on one side and the free surface at the top created by small energy, thus having two free surfaces and reducing the blasting intensity.

[0055] like Figure 4 As shown, with the middle row as the reference plane, the blast holes 3 on both sides of the middle row are inclined blast holes that are inclined towards the reference plane on a vertical plane perpendicular to the reference plane. The distance between the upper end of each blast hole 3 on both sides of the middle row and the reference plane is wider than the distance between the lower end and the reference plane. That is, on the vertical plane perpendicular to the reference plane, the blast holes, the upper and lower end faces of the blast holes, and the reference plane form a trapezoid that is wider at the top and narrower at the bottom. This arrangement makes the resistance line of the blast holes near the middle row gradually decrease as the blast holes extend downwards. It can make reasonable use of the free surface, reduce the clamping effect at the bottom of the blast holes, reduce blasting vibration, and is less likely to generate foundation. In addition, since the blast holes on both sides of the middle row are arranged in a horizontal and vertical direction, it is beneficial to control the back impact of blasting and to control the joint of the blast zone.

[0056] The horizontal component of the inclination direction of the boreholes in the middle row and the half-bore boreholes is consistent with the strike direction of the rock strata, while the horizontal component of the inclination direction of the boreholes on both sides is perpendicular to the strike direction of the rock strata.

[0057] To achieve good blasting results, reasonable borehole design is an important step. The borehole design method provided by this invention can provide new free surfaces for subsequent blasting, and the resistance line distribution after blasting is more uniform. It is less likely to produce large blocks, foundations and back impacts after blasting, thus reducing the harmful effects of blasting.

[0058] (2) Charge design

[0059] For borehole 2 in the middle row, the total charge is 50-60% of the hole depth. During charging, materials are spaced 1-2 meters apart. The lower section 5 has a charge of 60-65% of the total charge, and the upper section 6 has a charge of 35-40%. The purpose of the material spacing is to ensure that the two sections of explosive in the same borehole do not detonate sympathetically, thus achieving the designed blasting effect. The free surface conditions during blasting of the middle row of boreholes are relatively poor, requiring a larger amount of explosive to achieve the desired blasting effect. The lower part of the borehole is significantly constrained by the surrounding rock mass, thus requiring a larger amount of explosive. Using the charge ratio specified in this invention results in a better blasting effect.

[0060] For the half-hole 1, the total charge is one-third to one-half of the hole depth. Coupled charging without segmentation is adopted. Coupled charging can make the rock near the hole more fragmented, absorb a large amount of explosive energy, accelerate stress wave attenuation, reduce disturbance to the surrounding slope, and have a lower vibration velocity.

[0061] For the boreholes 3 located on both sides of the middle row, the total charge is 45-50% of the hole depth. During charging, materials are spaced 1-1.5m apart. The charge in the lower section 5 is 60-65% of the total charge, and the charge in the upper section 6 is 35-40% of the total charge. After the middle row of boreholes is blasted, it will provide a favorable free surface for the side row of boreholes, so the amount of explosive required for the side row of boreholes is less. The lower part of the borehole is significantly constrained by the surrounding rock mass, so a larger amount of explosive is required. Using the charge ratio specified in this invention, the blasting effect is better.

[0062] The existing technology uses vertical blast holes with the same area enclosed at the opening and bottom, and the upper free surface is better. Most of the explosive energy is used for breaking and throwing rocks. As the blast hole extends downward, the clamping effect of the blast hole increases, thereby increasing the disturbance effect of the explosive energy at the bottom of the blast hole on the surrounding rock, and consequently increasing the blasting vibration.

[0063] In the inclined borehole design provided by this invention, firstly, the free surface created by the half-hole with less energy is used for the first deep-hole blasting, creating a better single-sided free surface; secondly, in the inclined borehole, the area enclosed by the borehole opening is larger than the area enclosed by the bottom of the lower borehole, forming an inverted trapezoid shape that is larger at the top and smaller at the bottom. Therefore, as the borehole extends downwards, its resistance line decreases, meaning the required blasting energy decreases; as the borehole extends downwards, the clamping effect of the borehole increases, meaning the required energy decreases. By utilizing the gradually decreasing resistance line and the increasing negative effect of overcoming the clamping effect, the energy within the borehole can utilize the upper action surface to further break up the rock and throw it upwards to do work; this reduces the disturbance of energy to the surrounding rock and reduces blasting vibration, specifically as follows... Figure 5 As shown.

[0064] (3) Detonation sequence design

[0065] like Figure 6 As shown, when blasting all holes except the half-hole in the blasting starting area, the upper section 6 is blasted first and then the lower section 5 is blasted, with an interval of 40-65ms between the upper section 6 and the lower section 5. The two-shot method can reduce the energy generated at each moment of blasting, reduce the vibration of each blast, reduce the distance of flying rocks, and thus reduce the harmful effects of blasting.

[0066] One method to reduce blasting vibration is to reduce the amount of explosive in the same section. By using a two-stage blasting method in one borehole, the explosive in the borehole is changed from a single simultaneous blast to two blasts, thus reducing the amount of explosive in the same section. The time interval between the two stages must ensure that the blasting stress wave does not cause compaction of the explosive and alter its properties, while also allowing the blasting stress waves to cancel each other out. Therefore, an interval of 40–65 ms is chosen between the two stages. This ensures both the blasting effect of a single borehole and the overall blasting of rock.

[0067] The detonation sequence is as follows: first, detonate half of the blast hole 1; then, detonate the upper section of the middle row of blast holes located in the first row; and finally, detonate the lower section of the middle row of blast holes located in the first row and other blast holes within the initial blasting area segment by segment.

[0068] The total number of blasts in the initial blasting area is 1+2n, where n represents the number of blast holes in the initial blasting area excluding half-hole 1. The blasting process adopts a delayed blasting method, with an interval of 11-36ms between two consecutive blasts. During the blasting process, the interval time cannot be the same continuously, and the time interval between the middle or the last (1 / 2 to 3 / 4)*(1+2n) blasts is 11-15ms. Based on the half-cycle phase shift subtraction, the half-cycle corresponding to the main frequency of the blasting vibration wave is taken as the optimal delay time center. Considering the complexity of the frequencies contained in the blasting vibration wave, a better vibration velocity reduction can be achieved under the delay conditions proposed in this invention.

[0069] Only a reasonable detonation sequence can maximize the advantages of the borehole arrangement proposed in this invention. When the detonation sequence proposed in this invention is adopted, a deep trench will be generated after the middle row is blasted. Since the boreholes on both sides are arranged at an angle, the free surfaces on the upper and middle sides will be used reasonably during the blast, which can change the direction of the resistance line, enhance fragmentation, concentrate the blast pile, and achieve the effect of reducing the blast intensity.

[0070] Furthermore, the boreholes 3 located on both sides of the middle column are arranged in a matrix pattern.

[0071] Furthermore, within the initial blasting area, five or seven rows of blast holes of equal depth are arranged in a matrix pattern.

[0072] Furthermore, the parameters of each borehole within the initial blasting area are shown in the table below:

[0073] Table 1. Parameters for Deep Hole Blasting

[0074]

[0075] The inclination angle of the blast holes (including half-blast holes) in the initial blasting area is 70-80°, preferably 75°;

[0076] The diameter d of the blast holes (including half-blast holes) in the initial blasting area is 900-250mm; the depth (step height) of other blast holes in the initial blasting area, excluding half-blast holes, is >10m; the distance b between the upper ends of two adjacent rows of blast holes in the initial blasting area is (20-30)*d, and the distance a between the upper ends of two adjacent columns of blast holes is (20-30)*d; in the initial blasting area, the distance between the lower ends of two adjacent columns of blast holes on the same side of the middle column is (10-12)*d.

[0077] Furthermore, the spacer material used during loading is rock debris or crushed 1-2cm stones; using 1-2cm crushed stones for filling can reduce the loss of rock explosive per unit volume, make full use of the explosive energy, and reduce the distance of flying rocks during blasting.

[0078] Furthermore, such as Figure 1 As shown, the method for reducing vibration during inclined borehole trenching and blasting also includes the following:

[0079] (1-1) Piercing

[0080] After the borehole design is completed, a drilling machine is used to drill the holes. During drilling, the drilling angle needs to be confirmed by an angle gauge.

[0081] (1-2) Inspection of blast holes

[0082] After drilling is completed, the depth and spacing of the blast holes are confirmed using a tape measure, and the angle of the blast holes is measured using an angle meter.

[0083] (2-1) On-site construction

[0084] After loading the explosives into each borehole according to the design requirements, measure the remaining height of the borehole. Only proceed to the next step after the requirements are met. The upper and lower sections of each borehole need to be marked separately.

[0085] (3-1) When designing blasting according to the detonation sequence, it is necessary to meet the requirements of qualified network and adequate warning.

[0086] Furthermore, such as Figure 6 As shown, to illustrate the detonation sequence design proposed in this invention, in this embodiment, one half-bore hole and five rows of boreholes (boreholes 2-11) are set in the initial blasting area, with two boreholes in each row. According to the inclined borehole trenching blasting vibration reduction method proposed in this invention, the total number of blasts in the initial blasting area is 21. The specific detonation sequence and blasting delay time in this embodiment are shown in the table below:

[0087] Half-shot hole 0 Half-shot hole 0 Hole 2: Upper delay time 18 Hole 2: Lower delay time 60 Hole 3: Upper delay time 45 Hole 3: Lower stage delay time 89 Hole 4: Upper delay time 100 Hole 4: Lower stage delay time 164 Hole 5: Upper delay time 118 Hole 5: Lower stage delay time 178 Hole 6: Upper delay time 135 Hole 6: Lower stage delay time 190 Hole 7: Upper delay time 153 Hole 7: Lower stage delay time 205 Hole 8: Upper delay time 217 Hole 8: Lower stage delay time 261 Hole 9: Upper delay time 228 Hole 9: Lower stage delay time 272 Hole 10: Upper delay time 238 Hole 10: Lower stage delay time 284 Hole 11: Upper delay time 249 Hole 11: Lower stage delay time 297

[0088] Traditional deep-hole blasting vibrations can easily cause cumulative damage to the rock mass within the slope. For engineering sites where deep-hole blasting is frequently used, the mechanical strength of the surrounding rock mass is significantly reduced. In existing technologies, the blast holes are typically arranged as parallel vertical holes, and the explosives are loaded into the holes without segmentation. Blasting under this design results in a large back impact, with vibration intensity typically reaching 1.1–1.3 cm / s. After blasting, the looseness is 1.2–1.3, making excavation difficult. However, using the method provided by this invention, there is almost no back impact, and the vibration intensity can be reduced to 0.26 cm / s, with a looseness of 1.4–1.5. There is no problem of difficult excavation after blasting, significantly reducing the impact on surrounding slopes and important buildings, and showing great application prospects.

[0089] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for vibration reduction during blasting in inclined borehole trenches, characterized in that, A starting blasting zone is set up in front of the main blasting zone, which specifically includes the following: (1) Design of blast holes At least five rows of blast holes of equal depth are set in the initial blasting area, with the middle row of blast holes serving as the intermediate row; the blast holes on both sides in the initial blasting area are all inclined blast holes, and the blast holes in the same row are parallel to each other. On the side of the middle row away from the main blasting area, a half-shot hole is set. The depth of the half-shot hole is 1 / 2 of the depth of other holes in the initial blasting area plus 1~2 m. The holes in the middle row and the half-shot holes are all inclined holes that slope towards the main blasting area. The half-shot holes are parallel to the holes in the middle row. With the middle row as the reference plane, the blast holes on both sides of the middle row are inclined blast holes that are inclined toward the reference plane on a vertical plane perpendicular to the reference plane. The horizontal component of the inclination direction of the boreholes in the middle row and the half-bore boreholes is consistent with the strike direction of the rock strata, while the horizontal component of the inclination direction of the boreholes on both sides is perpendicular to the strike direction of the rock strata. (2) Charge design For boreholes in the middle row, the total charge is 50-60% of the borehole depth. During charging, spacer material is used as a gap. The charge in the lower section is 60-65% of the total charge, and the charge in the upper section is 35-40% of the total charge. For half-holes, the total charge is one-third to one-half of the hole depth, and a coupled charging method without segmentation is used. For boreholes located on both sides of the middle row, the total charge is 45-50% of the borehole depth. During charging, spacer material is used as a gap, with the lower section of charge being 60-65% of the total charge and the upper section being 35-40% of the total charge. (3) Detonation sequence design When blasting any blast holes other than half-cut blast holes within the initial blasting area, the upper section is blasted first, followed by the lower section, with an interval of 40-65ms between the upper and lower sections. The detonation sequence is as follows: first, detonate half of the blast hole; then, detonate the upper section of the middle row of blast holes located in the first row; and finally, detonate the lower section of the middle row of blast holes located in the first row and other blast holes within the initial blasting area segment by segment. The total number of blasts in the initial blasting area is 1+2n, where n represents the number of blast holes in the initial blasting area excluding half-cut blast holes; the blasting process adopts a delayed blasting method, with an interval of 11~36ms between two consecutive blasts; during the blasting process, the interval time cannot be the same continuously, and it must be in the middle or at the end (1 / 2~3 / 4). The time interval between (1+2n) explosions is 11~15ms.

2. The method for reducing vibration during inclined blast hole trenching and blasting according to claim 1, characterized in that, The distance between the upper end of each borehole located on both sides of the middle row and the reference surface is wider than the distance between the lower end and the reference surface.

3. The method for reducing vibration during inclined blast hole trenching and blasting according to claim 1, characterized in that, When loading explosives, the boreholes in the middle row are spaced 1-2m apart with material; the boreholes on both sides of the middle row are spaced 1-1.5m apart with material.

4. The method for reducing vibration during inclined blast hole trenching and blasting according to claim 1, characterized in that, The inclination angle of the blast holes in the initial blasting area is 70~80°; the diameter d of the blast holes in the initial blasting area is 900-250mm; the step height of the blast holes in the initial blasting area, except for the half-hole blast holes, is >10m; the distance b between the upper ends of two adjacent rows of blast holes in the initial blasting area is (20~30). d, the distance a between the upper ends of two adjacent rows of blast holes is (20~30). d; Within the initial blasting area, the distance between the lower ends of two adjacent rows of blast holes on the same side of the middle row is (10-12). d.

5. The method for reducing vibration during blasting and trenching in inclined blast holes according to claim 1, characterized in that, The spacer material used when loading explosives is rock debris or crushed 1-2cm stones.

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